Golf Club Head and Its Process of Making

ABSTRACT

A technique for making a golf club head comprises the following steps: (1) making a main body and a hitting face, both of which have a rough engaging bonding surface, separately; (2) bonding the main body to the hitting face through the engaging bonding surfaces with adhesive. The main body and the hitting face pf the present invention is bonded by adhesive, thereby the difficulty is reduced greatly, and the adhesive is easy to acquired and bonding can be achieved under low temperature, as well as the costs can be reduced, production efficiency can be improved and the manufacturing process is simplified. And the hitting performance of the golf club is also improved.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a golf club head, and more particularly to a technique for making the golf club head.

2. Description of the Prior Art

When playing golf, the golf ball will fly toward the hole after being hit by the golf club head. In addition to the influence of the golf club, the rebounding coefficient i.e. COR will also influence the hitting performance.

The metals used to make golf club head include: zinc alloy copper alloy, aluminum alloy, magnesium alloy, iron alloy, titanium alloy and compound materials, the hardness and the function of those metals are different, and different designs can obtain different hitting effects.

At present, the golf club head is mainly made by pressing and braze welding. Pressing is used to deform the golf club through extruding, which is only suitable for the iron golf club, and the structure formed by pressing is unvaried. Braze welding is used to bond the main body of golf club head and the hitting face with braze welding materials under high temperature, after the main body and the hitting face are manufactured with metals. The crucial portions such as hitting face is made of titanium alloy and other portions are made of stainless steel. Thereby the performance of the golf club head is almost the same as that of a golf club head made of titanium alloy. However, this kind of process has the following disadvantages, thus restricting the mass production of the golf club: (1) Special braze welding equipment is required; (2) The braze welding material is difficult to acquire; (3) The manufacturing process is complex. Chinese pat. No. 00107249.8 discloses a method of bonding a hitting board and main body for a golf club head, wherein several positioning ribs are disposed in the periphery of the main body of the golf club head, then the hitting board is used to cover the opening of the main body and is fixed by the positioning ribs. After that, a circle of braze welding material is arranged along the bonding edge of the main body and the hitting board, and the semifinal product is subjected to a high temperature heating treatment. Finally the positioning ribs and the protruded pulps are ground off. The technique is very complex.

Also, the main body and the hitting face can be bonded by adhesive, which is only used for bonding the body and the cover (the cover is made of carbon cloth or plastic) in prior art. Since the hitting face is the force-bearing part, the bonding strength of the body and the hitting face must be very strong, and the present bonding technique is unable to reach the requirement.

The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a technique for making a golf club head, wherein in the condition of the same bonding sizes, the strength of a main body and a hitting face after being bonded can be improved by more than 40%, thus reducing the coats, improving the efficiency, simplifying the technique and improving the hitting performance.

An aspect of the invention provides a golf club head. The said golf club head comprises a main body and a hitting face, wherein both the main body and the hitting face are made separately and have a rough engaging bonding surface respectively; and the main body and the hitting face are bonded together through the engaging bonding surface with adhesive.

Another aspect of the invention provides a process of manufacturing a golf club head. The said process comprises: (1) making a main body and a hitting face, both of which have a rough engaging bonding surface, separately; (2) bonding the main body to the hitting face through the engaging bonding surfaces with adhesive.

Preferably, the binding surface of the hitting face is engaged with the bonding surface of the main body exactly.

Preferably, the gap between the bonding surface of hitting face and the bonding surface of the main body is 0-0.5 mm.

Preferably, the method of making the bonding surfaces includes precision molding, forging or CNC processing.

Preferably, the main body and the hitting face can be respectively made of stainless steel and Ti alloy, or stainless steel and stainless steel, or stainless steel and compound metal, or Ti alloy and Ti alloy, or Ti alloy and compound metal.

Preferably, the bonding surfaces of the hitting face and the main body are formed with micro concave and protruded portions, whose height is <0.3 mm, after being processed.

Preferably, the bonding surfaces form rough surfaces by surface treatment processing method.

Preferably, the said surface treatment processing method includes high pressure sand spraying, or CNC (Computer Numerical Control) processing, or using acidic solution to corrode the surfaces, or precisely casting to create the rough surfaces.

Preferably, the shear strength of the adhesive is >25 Mpa.

Preferably, the adhesive is made of epoxy resin.

By using adhesive to bond the main body and the hitting face, the difficulty is reduced greatly, and the adhesive is easy to be acquired and it can achieve bonding under low temperature in the condition of the same bonding sizes, the strength of the main body and the hitting face after being bonded can be improved by more than 40% at a reduced cost and the production efficiency can be improved, and the manufacturing process can be simplified, Furthermore the performance of the golf club can also be improved.

The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiments in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 a-1 d are diagrams to show certain kinds of structures of bonding surfaces of a main body and a hitting face according to the present invention;

FIGS. 2 a and 2 b are diagrams of the main body and the hitting face before and after being processed according to the present invention;

FIG. 3 is a cross sectional view of the golf club head of FIG. 1 a; and

FIG. 4 is another cross sectional view of the golf club head of FIG. 1 d.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A process of manufacturing a golf club head comprises: (1) precisely making a main body 1 and a hitting face 2, both of which have a rough engaging bonding surface, separately; (2) bonding the main body to the hitting face through the engaging bonding surfaces with adhesive.

The main body 1 and the hitting face 2 can be respectively made of stainless steel and Ti alloy, or stainless steel and stainless steel, or stainless steel and compound metal, or Ti alloy and Ti alloy, or Ti alloy and compound metal. The metals are bonded by adhesive, so even though the adhesive is very strong, it is hard to bond the main body land the hitting face 2 strongly. However, the main body 1 and the hitting face 2 of the present invention are formed with a engaging bonding face respectively, preferably a concave section and a protruded section which can be engaged with each other, thus the main body 1 and the hitting face 2 can be bond strongly. The engaging structure also plays a role in restriction, which can restrict the stress being pressed on the sticking layer that is vertical to the bonding surface so as to reduce the possibility of falling off. FIGS. 1 a-1 d shows the structure of four kinds of bonding surfaces, however, in addition to those structures, the bonding surfaces can also be of other structures. The structures as shown in FIGS. 1 a-1 d include the concave section and the protruded section that can be engaged with each other (the position of the concave section and the protruded section is changeable): the bonding surfaces of the main body 1 and the hitting face 2 as shown in FIG. 1 a is formed with a protruded section respectively that are relative to each other so as to form an L-shaped head, and the concave and the protruded section of the L-shaped heads are engaged with each other. The main body 1 as shown in FIG. 1 b is formed with a groove so as to form an L-shaped head, and the edge of the hitting face 2 is engaged in the groove exactly. The head of the main body 1 as shown in FIG. 1 d is formed with a concave-shaped bonding face, and the hitting face is formed with an L-shaped head that is engaged in the concave-shaped bonding face exactly. The head of the main body 1 as shown in FIG. 1 d is formed with a concave-shaped bonding face, and the head of the hitting face 2 is formed with a protruded-shaped bonding face. When the concave section is engaged with the protruded section, the gap between the bonding surfaces is preferably 0-0.5 mm, and the width of the bonding surface is 0-10 mm. The method of making the bonding surface includes precisely molding, or forging or CNC processing.

In order to improve the bonding strength, the bonding surfaces should be processed to be rough, as shown in FIGS. 2 a and 2 b. After being processed, the smooth surface 3 of the bonding surface is formed with micro concave and protruded portions, and the depth of the portions are smaller than 0.3 mm. Such processing method includes high pressure sand spraying (such as AL₂O₃ sand and steel ball), or CNC processing, acidic solution to corrode the surfaces, or precisely casting to create the rough surfaces.

By using the said bonding surface and through the surface rough treatment of the body 1 and the hitting face after being stuck can be improved by more than 40%.

Finally the main body 1 and the hitting face 2 are bonded by adhesive, and the shear strength of the adhesive should be ≧25 Mpa. At present, the adhesive is made of epoxy resin, and the solidification technique of the adhesive is determined by the kind of (the) adhesive being used. After the adhesive is solidified, an organic mesosphere is formed between the main body 1 and the hitting face 2, which is serves to reduce shock so as to improve the performance o the golf club.

Since the hitting face is the most important factor that influences the hitting performance of the golf club, the technique of the present invention is mainly aimed at how to bond the main body and the hitting face. However, this invention can also be used for bonding other regions of the club head

The steps of Embodiment 1 are as following:

First, precisely molding a main body 1 with 17-4 stainless steel and a hitting face 2 with 6-4 Ti, the bonding surfaces of the main body 1 and the hitting face 2 being formed with a protruded section respectively that are relative to each other so as to form an L-shaped head, and the concave section engaging with the protruded section exactly (as shown in FIG. 1 a);

Second, CNC processing cooperating with gap arithmetical ratio controlling +0.1 mm/−0 mm;

Third, surface treating by spraying each bonding face with AL₂O₃ so as to form micro concave and protruded portions, and the height of protruded portion being <0.3 mm;

Fourth, smearing the adhesive, whose shear strength is ≧25 Mpa, on the concave and protruded sections of the main body 1 and the hitting face 2, and then engaging the main body 1 with the hitting face 2 through the concave and protruded section;

Fifth, solidifying the adhesive through heating in a oven for 1.5 hours under the temperature of 120' C so that the main body 1 is bonded to the hitting face 2 (as shown in FIG. 3)

The steps of Embodiment 2 is as following:

First, precisely molding a main body 1, whose head is formed with a concave-shaped bonding surface, with 6-4TI, and forging a hitting face 2, whose head formed with a protruded-shaped bonding surface, with 6-4Ti; and the bonding surfaces engaging with each other exactly (as shown in FIG. 1 d), the gap between the bonding surfaces being <0.5 mm; and the bonding surface of the main body 1 of 6-4Ti being directly formed with micro concave and protruded portions, whose height is <0.3 mm, when being precisely molded;

Second, spraying the hitting face 2 of 6-4Ti with steel balls so as to form micro concave and protruded portions whose height is <0.3 mm;

Third, smearing the adhesive, whose shear strength is ≧25 Mpa, on the concave and protruded sections of the main body 1 and the hitting face 2, and then engaging the body 1 with the hitting face 2;

Fourth, solidifying the adhesive through heating in a oven for 40 minutes under the temperature of 140' C, thus the main body 1 being bonded to the hitting face 2 (as shown in FIG. 4).

While we have shown and described various embodiments in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention. 

1. A golf club head, comprising a main body and a hitting face, wherein both of the main body and the hitting face being made separately and having a rough engaging bonding surface, and the main body and the hitting face being bonded together through the engaging bonding surfaces with adhesive.
 2. A process of manufacturing a golf club head, comprising: (1) making a main body and a hitting face separately, both of which have a rough engaging bonding surface, (2) bonding the main body to the hitting face through the engaging bonding surfaces with adhesive.
 3. The process of manufacturing a golf club head as claimed in claim 1, wherein the bonding surface of the hitting face is engaged with the bonding surface of the main body exactly.
 4. The process of manufacturing a golf club head as claimed in claim 1, wherein the gap between the bonding surface of hitting face and the bonding surface of the main body is 0-0.5 mm.
 5. The process of manufacturing a golf club head as claimed in claim 1, wherein the method of making the bonding surfaces includes precision molding, forging or CNC processing.
 6. The process of manufacturing a golf club head as claimed in claim 1, wherein the main body and the hitting face can be respectively made of stainless steel and Ti alloy Ti alloy, or stainless steel and stainless steel, or stainless steel and compound metal, or Ti alloy and Ti alloy, or Ti alloy and compound metal.
 7. The process of manufacturing a golf club head as claimed in claim 1, wherein the bonding surfaces on the hitting face and the main body are formed with micro concave and protruded portions, whose height is <0.3 mm, after being surface processed.
 8. The process of manufacturing a golf club head, wherein the bonding surfaces form rough surfaces by surface treatment processing method.
 9. The process of manufacturing a golf club head as claimed in claim 8, wherein the said surface treatment processing method includes high pressure sand spraying, or CNC processing, or using acidic solution to corrode the surfaces, or precisely casting to create the rough surfaces.
 10. The process of manufacturing a golf club head as claimed in claim 1, wherein the shear strength of the adhesive is ≧25 Mpa.
 11. The process of manufacturing a golf club head as claimed in claim 1, wherein the adhesive of made of epoxy resin. 